Problems with UFH
- Thread starter lup31337
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What you are aiming to do is to get the UFH output higher as your u/stairs roomstat isn't achieving its setpoint temperature, generally, you just set the mixed flowtemperature to a max of say 45ish (mindfull of floor covering max temperature), you then adjust the flowrates to suit individual rooms,you cant achieve this with this system for one reason or another so not alot can be done IMO, what you really want to do is to reduce the recirc rate, Normally you might have a flowrate of say 2.0LPM through each loop with a manifold flow/return temp of 40C/33C, dT 7C, which will result in a UFH output for a 10 loop system of 10*2*60*7/860, 9.77kw, if you want to play around with flowrates, pump speeds or whatever yourself you can then see the UFH output by (adding the individual flowrates) X 60 X UFH dT/860), kw.
Its strange but the Tio mixer below shows the flow and return reversed??.
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Its strange but the Tio mixer below shows the flow and return reversed??.
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After I increased the boiler water temp to 60C everything worked as intended. Took a while to draw that conclusion, as UFH doesn't heat up the room as fast as radiators. However, now I have 22-23C ambient upstairs. I was asking about the flow rates as an optimization. Maybe making the system more efficient.
You can adjust the flowrates individually for each loop, but if the return to the boiler is very low then its operating very efficiently
What kind of manifold temperatures are you getting now?, you might just take two more temps to see how much HW is bypassing to the boiler return, in post #12 where you have a red arrow can you take the temp just to the left of this and down a bit on the return to the boiler and also the temp at the copper pipe on the manifold return, how much is the bypass open now on the u/stairs manifold?
What kind of manifold temperatures are you getting now?, you might just take two more temps to see how much HW is bypassing to the boiler return, in post #12 where you have a red arrow can you take the temp just to the left of this and down a bit on the return to the boiler and also the temp at the copper pipe on the manifold return, how much is the bypass open now on the u/stairs manifold?
Here is, IMO, a proper type (TIO) mixing valve that uses external mixed flow temperature (manifold flow temperatue) measurement using a capillary sensor.
Apart from the external sensing, it works almost exactly the same as any TMV, it has a shuttle valve that controls the mixing by changing the hot/cold flow rates, additionally, it also has a loading valve designed to maintain the required mixed temperature between low and high UFH demands.
Apart from the external sensing, it works almost exactly the same as any TMV, it has a shuttle valve that controls the mixing by changing the hot/cold flow rates, additionally, it also has a loading valve designed to maintain the required mixed temperature between low and high UFH demands.
Just noticed a different problem. All thermostats reached the designated temperature. All actuators closed and circulation pumps closed as well. No demand from the boiler. Boiler starts till it reaches 66 degrees and shut down. Restarts after 10 minutes. Pipes are hot, main flow and return pipe, manifold etc. Every pipe is hot while the system is shut down but the boiler keeps firing for some reason.
Maybe the automation is not wired correctly? And the boiler fires independently? I searched the manual and found a setting where I can change the restart cycle anywhere from 3 minutes to 45 mins. So, I can make it longer. Though that doesn't solve the issue, it just makes it less worse.
Maybe the automation is not wired correctly? And the boiler fires independently? I searched the manual and found a setting where I can change the restart cycle anywhere from 3 minutes to 45 mins. So, I can make it longer. Though that doesn't solve the issue, it just makes it less worse.
I just realized that the boiler is not wired to anything. It's set to 60C. If the temperature drops to 54C, it starts. If it reaches 66 it stops and restarts if 10 mins have passed and temp is lower than 54.
The thermostats just control the actuators and the pump and don't trigger the boiler.
I'm speechless. This house has thermostats even in the bathrooms. However, they are not wired to the boiler ...
I don't know what solution is there because there is no convenient way to wire from the manifolds of both floors to the boiler. It's out of the question. Maybe there are some wireless devices that communicate between each other and when the UFH command center triggers this device it send a wireless signal to a similar device that will trigger the boiler's relay.
The thermostats just control the actuators and the pump and don't trigger the boiler.
I'm speechless. This house has thermostats even in the bathrooms. However, they are not wired to the boiler ...
I don't know what solution is there because there is no convenient way to wire from the manifolds of both floors to the boiler. It's out of the question. Maybe there are some wireless devices that communicate between each other and when the UFH command center triggers this device it send a wireless signal to a similar device that will trigger the boiler's relay.
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